Steam control system for locomotive cylinders and steam chests



May 18, 1943 c. STERN 2,319,642

STEAM CONTROL SYSTEM FOR LOCCMOTJEVE CYLINDERS AND STEAM CHESTS Filed Sept; 20, 1941 2 Sheets-Sheet 1 1O ez''ul 7 O INVENTOR I CHA n55 STERN BY 81 945x62 ATTORNEY c. STERN 2,319,642

STEAM CONTROL SYSTEM FOR LOCOMOTIVE CYLINDERS AND STEAM CHESTS May 18, 1943 Filed sept. 26, 1941 2 Sheets-Sheet 2 INVENTOR CHAEL 5 5 TEEN 'ATTORNEY Patented May 18, 1943 STEAM CONTROL SYSTEM FOR LOCOMO: TIVE CYLINDERS AND STEAM CHES-TS Charles Stern, Jersey City, N. J. Application September 20, 1941, Serial No. 411,728

Claims.

This invention relatesto steam control system for locomotive cylinders and valve chambers while locomotive is drifting or coasting and at rest.

An object of this invention is to provide an automatic steam control system for a locomotive, of the character described, comprising means for eliminating formation of vacuum in the cylinders, and preventing formation of carbon and assuring positive lubrication with a minimum of steam consumption, means being further provided to protect the locomotive against accumulated pressure in the cylinders or valve chambers while standing in the terminal or roundhouse.

Another object of this'invention is to provide in a system of the character described, means for admitting auxiliary steam' at" a predetermined pressur to the valve chambers and steam cylinders immediately upon shutting off of the main throttle, whereby at no time is steam absent from the valve chambers and cylinders, thus effective: 1y preventing admission of air to the valve chambers and cylinders, flashing of oil, and formation of carbon, the arrangement being such that the auxiliary steam is admitted to the cylinders and cylinder valves automatically and without the attention of the locomotive operator.

Still another object of this invention is to provide in a system of the character described, means to admit steam direct to the admission ports of the cylinders and to the valve chambers regardless of the position of the valve, while drifting, thereby preventing admission of air. and gases therein and providing sufiicient steam pressure for atomizing the oil and cushioning the pistons in the-cylinders, rods, bushings and all reciprocating parts of the steam engine,

Yet another object ofthis invention is to pro' vide in a system of the character de'scribed, a drifting throttle and balancing steam valve which shall be relatively inexpensive to manufac ture, positive in operation, and practical and efficient to a high degree in use.

Other objects of this invention will in part be obvious and in part hereinafter pointed out. The invention accordingly consists in the features of construction, combinations of elements, and arrangement of parts which will be exemplified in the construction hereinafter described, and of which the scope of application will be indicat-ed in the following claims.

In the accompanying drawings, in which is shown one of the various possible illustrative embodiments of this invention,

Fig. l is a. side, elevational view of a locomotive provided with steam control system for drifting locomotive, embodying the invention;

Fig. 2 is a front, elevational view of the locomotive shown in Fig. 1; Y Fig. 3 is an elevational, cross-sectional view through a steam cylinder, drifting throttle and balancing steam valve, embodying the invention; Fig. 4 is a view similar to Fig. 3," but diSClOS ing the position of the apparatus while the locomotive is drifting; Fig. 5 is, a cross-sectional 5-5 of Fig. 4; and i v Fig. 6 is an elevational, cross-sectional view. of air operatedvalve for actuating a valve control-1 view taken on line ling admission of low pressure steam to steam cylinder and steam chest while locomotive .is

drifting. I

Referring now in detail to the drawings, Ill designates a locomotive provided with a steam control system,. embodying the invention, for the locomotive cylinders and valve chambers while the locomotive is drifting or standing still. The locomotive I0 is provided with the usual steam cylinders H on opposite sides of the locomotive, each provided with a valve chamber 12 in which there reciprocates the usual spool valve l3.

Each valve chamber or steam chest is pro vided with a steam balancing valve 25 mounted thereon Each balancing valve 25 comprises a housing 2511 having an inner cylindrical surface 26 formed with an inwardly extending shoulder 26a at its upper end and being open at the bottom. At the upper end of the cylindrical surface 26 is a cylindrical surface 2% of reduced diameter co-axial with the surface 26. At the upper end of the surface 261) is a valve seat 26c. Extending upwardly from the valve seat 260 is a tubular portion 21 forming a dome chamber 25b and provided with a screw threaded open;

ing Tia at one side. The upper end of tubular portion 2115' closed by a screw plug 211). The housing 25:; is formed with a pair of diametrical ly opposed, symmetrical, cored passages 28 communicating at their upper ends with the surface 262) and terminating short of the lower end of the casing 25a. The casing 25a is formed with external openings 28a communicating with the lower ends of said cored passages 28.

The housing 25a as shown in Fig. 5 of the drawings, is formed with a second pair of diametrically opposed, symmetrical cored passages 28c disposed in a plane perpendicular to the plane of the passages 28 and communicating at their upper ends with the surface 26b and at their lower ends with the cylinder Zii. Said passages 280 thus connect chamber 25b in the dome with chamber 250 within cylinder 26. The lower end of the housing 25a (chamber 250) is closed by a member 2807 having a cylindrical wall 286 projecting upwardly into chamber 250 and formed with two pairs of diametrically opposed openings 28]. One of said pair of openings is shut by the cylindrical surface 26, and the other pair of openings 28f registers with the lower ends of the cored passages 280, as shown in Fig. 5 of the drawings.

Thus, member 28d may be attached to the lower end of the casing a in any of four angular positions, so that there will always be two openings 28] registering with the passages 28c. Member 28d may be fixed to the casing 25a in'any suitable manner. Said member is formed with a central opening 28g receiving a nipple or pipe 2872, the lower end of which is screwed within the top of the valve chamber l2.

Slidably mounted within casing 25a is a plunger or valve 29 havingan enlarged face 23a at its lower end, slidably engaging within chamher 250, whereas, the body of the valve slidably engages the suriaoe 26b. When the plunger '29 is in its up position, as shown inFig. '3, it is seated on valve 260 to close the passages 29, 28c; and when said valve is in its down position as shown in Fig. 5, the passages 28, 280 are open establishing communication between the dome chamber 25b, the lower chamber 250 and hence pipe 28h through the openings 28a.

Screwed within the openings 28a are pipes 29b which are connected at their lower ends to the admission ports 290 of the steam cylinder 3 When steam is admitted through opening 21a into the top of the valve 25, in the manner hereinafter appearing, steam may pass through the passages .28, 280 when the plunger 29 is in its down position, as shown in Fig. 5, to feed steam, from the dome of the boiler, .as will be .seen hereinafter, .both tothe steam chest l2 and to the admission ports of the steam cylinder Within .each valve 25 is a spring 296 interposed between the plunger 29 and the plug 28 to exert downward pressure on said plunger.

Normally when the locomotive is running and the throttle is open, steam from the pipes 59 under main throttle pressure supplies suflicient pressure within the steam chests to raise the valves ,or plungers 29 against the pressure of the springs .29e to cut off communication between the pipes 2%. It will now be understood that normally when the locomotive is running, there is no by-pass between the admission ports of the cylinders through the pipes 29b, thus preventing waste of steam.

The domes of the valves 25, are interconnected by a pipe 35, the ends of which are received into openings 21. Communicating with said pipe is a pipe 36 leading to the dome of the locomotive and receiving steam therefrom at boiler pressure. Interposed in said pipe 36 is a steam valve 31 adapted to be opened upon moving upwardly, in the manner hereinafter appearing, a valve stem 31 projecting below said valve.

Means is provided for automatically moving the valve stem 38 upwardly to open the steam valve 3-! and admit steam at boiler pressure to pipes 36 and 35, when the throttle is shut off, for example, when the locomotive is coasting, or upon the train approaching a station, or whenever the train is brought to a halt. To this end,

there is mounted on the locomotive and below the steam valve 37, an air operated valve 39 comprising a fixed cylindrical housing 39a, closed at the bottom by a plug 39b. Connected to said plug 39b is a pipe 390 adapted to supply air under pressure to the interior of said housing. Said housing 39a has a top wall formed with a central opening 39d.

Slidably mounted within said housing is a member 40 having a reduced portion projecting through opening 39d and normally pressed downwardly by a compression spring 49a interposed between said member and the top wall of the housing 39a. Said member 49 may be hollow and filled with oil, for the purpose of lubrication,-the ,wall of said member being formed with small openings 4% to permit the oil to pass to the inner surface of housing 39a. The upper end of the "hollow member 40 may be closed by an adjusting screw 4| adapted to contact the lower end of the valve stem 38.

When there is no air supply through pipe 390 to the housing 390%, member 40 is held down by spring 40a and the steam valve 31 is closed.

.c When air under pressure however is supplied to pipe 390, in the manner hereinafter explained, member 49 will be moved upwardly against the pressure of spring 40a to lift the stem 38 and open the steam valve 31 to admit steam under boiler pressure to pipe 36, and hence through pipe 35 to the steam control valves 25.

The airp'ipe 39c leads to a chamber 4| having a bottom wall 4 la and a top wall 4 lb. The bottom wall 4 la, is formed with a vertical through opening 4|c having a valve seat at its upper end. Slidably mounted in said through opening is a valve 4|d having a grooved stem within said open g, and a head 4|e adapted to be seated on said valve seat.

A compression spring 4| 1 normally holds the valve 41d down in its closed position. Integrally formed with chamber 4| is a second chamber 42 to which is connected a pipe 42a leading to the cab and then to the main air reservoir 42b. There is interposed in said pipe 420., a valve 420,- located in the cab. The wall between chambers 4| and 42 is provided with an opening 42d, and the bottom wall 4|a of the chamber 4| is formed with an opening 42c aligned with said first opening. a I

,Slidab-ly mounted in said openings is a valve 42- having a head at its upper end adapted to close the opening 42d. A coil compression spring 42g normally retains the valve '42 in closed position. When the valve 42 is closed, no air is supplied to the pipe 390 and the stem valve 31 is closed.

Means is provided however for automatically opening the valve 42 j and closing valve 4|cl, upon shutting off the main throttle, whereby to open steam valve '31 and supply steam to the steam balancing valves 25.

To this end, there is supported by a bracket 42h, fixed to the steam chest at the right of the locomotive (looking at Fig. 2), or in any other suitable manner, a steam control valve 43. Said steam control valve 43 comprises a member 44 having a pair of spaced, coaxial, oppositely extending cylindrical portions 45 and 46, the latter being of somewhat greater diameter than the former. The cylindrical portion 46 has a back wall 46a formed with a central opening 461). The outer end of cylinder 4t is closed by an end wall 41 forming a chamber 48 therewith. Said end wall 41 has an opening Connecting said opening with the main steam pipe 59, is a pipe 49.

The cylindrical wall 46 is formed, mediately the ends thereof, with an opening 460, connected by a reduced pipe 52 with said pipe 35. Communicating with chamber 48, adjacent the back wall 45a, is a pressure check valve 55 which may be set to open at a predetermined pressure, preferably somewhat above atmospheric pressure, for the purpose hereinafter appearing.

The member 44 is formed with a chamber 58 surrounding the cylindrical member 45 and closed by an end wall 59. interconnecting the cylindrical wall 45 with the outer wall of the cham ber 58, is an exhaust port 60. Said chamber may also be provided with a condensation check ordrain valve 6|.

Chambers 4|, 42 are located between cylinder 46 and chamber 58 and supported on member 43 in any suitable manner.

Slidably mounted onthe member 44 formciprocation, is a member 62, to control valves 41d and 42f, and comprising a piston 55, within the cylindrical member 46, a piston 66, within the cylindrical wall 45, and an axial piston cam 61 interconnecting said pistons. Chamber 58 is interconnected to chamber 48 by pipe 68 closed at one end by spring pressed check valve 69 located on cylinder 45. The piston cam 61 is formed with a pair of spaced, raised cam portions and H disposed between the cylinders 45, 45 and adapted to operate air valves 41d, 42f.

Normally, when the locomotive is running and the main throttle is open, steam from main steam pipe 50 passes through pipe 49 to chamber 48, holding control member 52 to the right. In this position, piston 65 closes opening 450, and piston 66 closes the exhaust port 60. Steam passes through chamber 48, passage 68 and valve,69 (which is unseated), to chamber 58 where steam is trapped. Member 62 will stay to the right because piston 55 is of greater area than piston 66. In this position of said member 62, raised portion 10 of piston cam 61 will lift valve 4I d to exhaust any air pressure that may be in pipe 390, while valve 42 will be held down by spring 420 and air pressure, to close chamber 42 and prevent air from the main reservoir from passing to pipe 390.

When the main throttle is shut to coastthe locomotive or to bring the same gradually to a stop, pressure in main steam pipes 50 and in the steam chests is reduced below the pressure of the steam trapped in chamber 58, causing control member 62 to move to the left, from the position of Fig. 3 to the position of Fig. 4. This operation will lift or open valve 42 and permit valve 41d to drop to closing position. Air from the main reservoir will then pass through pipe 42a, chambers 42 and 4| to pipe 39c, for lifting valve mein-' ber 40 to open steam valve 31 and admit steam under boiler pressure from the dome ofithe locomotive to pipes 35 and 35 to the domes of valves" passages 280 to the middle of the steam chests regardlessof the positions of the spool valves-l3.

' This operation also seals the back of piston -55 since said piston'closes the passage 68. Openin 46b in back wall 45a, is also sealed by collar Ill on piston cam 61. Exhaust port 60 is also opened to exhaust steam from chamber 58. Opening'46c however is uncovered to admit steam from pipe 35 to pipe52, and to, the back of piston 65, to keep. the controlfmember 62 to the left. The steam behind piston 55'is maintained at the pre-v determined pressure of check valve 55. r

The steam supplied to the steam chests and cylinders. prevents vacuum in the cylinders, and formationg'of carbon and atomizes the oil to assure positive lubrication with a minimum of steam consumption.

As the locomotive slows down, pressure builds up in the steam chest slightly, and hence also in main steam pipe 50. Steam passing through pipes 49 hence increase pressure on the left side of pistons 65 sufficiently to overcome the pressure on the opposite side of said pistons, causing the control valve members 62 to move .to the right. This operation opens valves 4 l d and closes valves 42 to exhaust air pressure from pipe 390 and close steam valve 31 to shut on supply of steam from the dome to valves 25.

The plungers 29 in valves 25, however, remain in their downmost position since the pressure in the steam chests is not suflicient to raise said plungers against springs 29c. Since the plungers remain down, the steam chests remain in direct communication with the exhaust passages of the locomotive, providing for a release of any accumulated pressure in the steam chests, and protecting the locomotive against movement in case of leaky throttle while standing in the round house or terminal, or in case the steam valve 31 is not completely shut off. Should there be a leak in the main throttle causing pressure to accumulate in the steam chests, steam will pass upwardly through pipe 28h and passages 28c, around plungers 29, and through pipes 29b to the cylinders.

The cylinders H may be provided with usual relief cylinder cocks connected by pipes 8| to pipe 42a.

When the locomotive is standing still for some time, the cab valve 420 is closed and the cylinder cocks 8B are open to exhaust the wet steam from the steam cylinders. Upon starting, the valve 420 is opened to close the cylinder cocks, and this action automatically supplies air to pipe 42a and chamber 42. The main throttle is then opened up to lift the plunger 29 to prevent bypass of steam through pipes 291), and to shut passage of steam around the plunger. The control system is then in position for automatic operation when the main throttle is next shut off."

Usually when a locomotive ties up at a terminal or in a round house, the locomotive operator opens the cylinder cocks. This action shuts off the air supply and prevents possibility of opening of the steam valve 31, and hence prevents admission of steam to the valve chambers and steam cylinders. The operator usually also shuts ofi the air pump, and this action likewise cuts off the air pressure which is necessary to operate the steam valve 31, thereby giving an additional safety against accidental movement of the loco motive at the terminal or in the round house.

When the cylinder cocks Bil are closed by opening of cab valve 420, air pressure will be supplied to chamber 42 through pipe 42a which leads to the cylinder cocks as well as to said chamber.

This action by the locomotive operator supplies air pressure to the drifting throttle control valve and it is now ready to function when needed. Thus, the operator cannot neglect to supply the necessary air pressure for opening the valve 38 the next time the locomotive coasts since the cylinder cocks 80 must be closed by opening the valve 420 in order to start the locomotive.

When the main throttle valve is opened, steam is admitted through pipe 49 into the cylinder 46 unseating the non-return check valve 69, and supplying steam to the pressure chamber 58. In this position, the plungers 29 in the steam balancing valves 25, are raised by steam pressure from the steam chest overcoming the pressure of springs 29c and preventing by-pass of steam around the steam balancing valves.

The plugs 21b and pipes 49 may be interconnected by pipes 90 connected by pipes 9| to any suitable supply of oil, for the purpose of lubrication.

The cylinder cocks may be operated by steam instead of air.

' It will thus be seen that there is provided a device in which the several objects of this invention are achieved, and which is well adapted to meet the conditions of practical use.

, As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In combination with a steam cylinder and a steam chestfor said cylinder, a steam balancing valve comprising a casing, a chamber within said casing, pipes connecting said casing with the admission ports of said cylinder, passages interconnecting said pipes with said chamber, said casing being formed with a second chamber, passages within said casing interconnecting the second chamber with the first chamber, means to connect said second chamber with the steam chest, and a plunger within said casing adapted in one position thereof to close said passages to prevent passage of steam between said pipes and also to prevent passage of steam from said first chamber to said pipes and to said second chamber, and in another position thereof being adapted to open said passages to permit flow of steam from said first chamber to said second chamber and steam chest, and from said first chamber to said pipes.

2. In combination with a steam cylinder and a steam chest for said cylinder, a steam balancing valve comprising a casing, a chamber within said casing, pipes connecting said casing with the admission ports of said cylinder, passages interconnecting said pipes with said chamber, said casing being formed with a second chamber, passages within said casing interconnecting the second chamber with the first chamber, means to connect said second chamber with the steam chest, a plunger within said casing adapted in one position thereof to close said passages to prevent passage of steam between said pipes and also to prevent passage of steam from said first chamber to said pipes and to said second chamber, and in another position thereof being adapted to open said passages to permit fiow of steam from said first chamber to said second chamber and steam chest, and from said first chamber to said pipes, means to supply steam to said first chamber, cylinder cocks on said steam cylinder, means to supply air to operate said cylinder cocks, means to control said air supply, and means controlled by the means to control said air supply, to control said means to supply steam to the first chamber.

3. A steam balancing valve comprising a casing formed with a chamber at the upper end thereof, and an internal cylindrical chamber, a passage connecting said chambers, said casing being formed with a pair of external openings, passages connecting said openings with said first chamber, a plunger within said cylindrical chamber adapted to close said passages in one position thereof, to close communication between said first chamber and said openings and said second chamber, and in another position thereof being adapted to open communication between said first chamber and said openings, and between said first chamber and cylindrical chamher, and spring means to normally maintain said plunger in the second position thereof.

4. A steam balancing valve comprising a casing, having an internal cylindrical chamber open at the bottom, a cylindrical surface of reduced diameter, above said chamber, and co-axial therewith, a valve seat at the upper end of said cylindrical surface of reduced diameter, and a chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with passages connecting said openings with said cylindrical surface, and said wall of said casing being further formed with a pair of passages connecting said cylindrical surface with said cylindrical chamher, a plunger within said casing having a flange within said cylindrical chamber, and a body within said cylindrical surface, and a portion adapted to seat on said valve seat, and a member closing the bottom of said cylindrical chamber.

5. A steam balancing valve comprising a casing, having an internal cylindrical chamber open at the bottom, a cylindrical surface of reduced diameter, above said chamber, and co-axial therewith, a valve seat at the upper end of said cylindrical surface of reduced diameter, and a chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with passages connecting said openings with said cylindrical surface, and said wall of said casing being further formed with a pair of passages connecting said cylindrical surface with said cylindrical chamber, a plunger within said casing having a flange within said cylindrical chamber, and a body within said cylindrical surface, and a portion adapted to seat on said valve seat, and a member fixed to said casing closing the bottom of said cylindrical chamber, said member having a cylindrical flange projecting up into said cylindrical chamber and formed with openings registering with the passages which connect said cylindrical chamber with said cylindrical surface.

6. A steam balancing valve comprising a casing, having an internal cylindrical chamber open at the bottom, a cylindrical surface of reduced diameter, above said chamber, and co-axial therewith, a valve seat at the upper end of said cylindrical surface of reduced diameter, and a chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with passages connecting said openings with said cylindrical surface, and said wall of said casing being further formed with a pair of passages connecting said cylindrical surface with said cylindrical chamber, a plunger within said casing having a flange within said cylindrical chamber, and a body within said cylindrical surface, and a portion adapted to seat on said valve seat, a member closing the bottom of said cylindrical chamber, and spring means to press said plunger downwardly in said casing.

'7. In combination with a steam cylinder and a steam valve therefor, a steam balancing valve comprising a casing having a wall formed with an internal cylindrical chamber, means to connect said chamber with the steam valve, said casing being furthermore formed with a cylindrical surface of reduced diameter above said cylindrical chamber and with a valve seat at the upper end of said cylindrical surface, and with a dome chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with cored passages connecting said openings with said cylindrical surface, the wall of said casing being furthermore formed with a passage connecting said cylindrical surface with said cylindrical chamber, a plunger slidably mounted within said casing having a flange portion within said cylindrical passage, and a body portion adapted to be received within said cylindrical surface, and a portion at its upper end adapted to contact said valve seat, said plunger being adapted to close said passages in the up position thereof and to uncover said passages in the down position thereof, and means to connect said openings with the admission ports of said steam cylinder.

8. In combination with a steam cylinder and a steam valve therefor, a steam balancing valve comprising a casing having a wall formed with an internal cylindrical chamber, means to connect said chamber with the steam valve, said casing being furthermore formed with a cylindrical surface of reduced diameter above said cylindrical chamber and with a valve seat at the upper end of said cylindrical surface, and with a dome chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with cored passages connecting said openings with said cylindrical surface, the wall of said casing being furthermore formed with a passage connecting said cylindrical surface with said cylindrical chamber, a plunger slidably mounted within said casing having a flange portion within said cylindrical passage, and a body portion adapted to be received within said cylindrical surface, and a portion at its upper end adapted to contact said valve seat, said plunger being adapted to close said passages in the up position thereof and to uncover said passages in the down position thereof, means to connect said openings with the admission ports of said steam cylinder, and a spring interposed between said plunger and the top of the casing.

9. In combination with a steam cylinder and a steam valve therefor, a steam balancing valve comprising a casing having a wall formed with an internal cylindrical chamber, means to connect said chamber with the steam valve, said casing being furthermore formed with a cylindrical surface of reduced diameter above said cylindrical chamber and with a valve seat at the upper end of said cylindrical surface, and with a dome chamber above said valve seat, the wall of said casing being formed with a pair of diametrically opposed, external openings and with cored passages connecting said openings with said cylindrical surface, the wall of said casing being furthermore formed with a passage connecting said cylindrical surface with said cylindrical chamber, a plunger siidably mounted within said casing having a flange portion within said cylindrical passage, and a body portion adapted to be received within said cylindrical surface, and a portion at its upper end adapted to contact said valve seat, said plunger being adapted to close said passages in the up position thereof and to uncover said passages in the down position thereof, means to connect said openings with the admission ports of said steam cylinder, a spring interposed between said plunger and the top of the casing, and means to supply steam to the dome chamber of said casing.

10. In combination with a steam cylinder and a steam valve therefor, a steam balancing valve comprising a casing having a wall formed with an internal cylindrical chamber, means to connect said chamber with the steam valve, said casing being furthermore formed with a cylindrical surface of reduced diameter above said cylindrical chamber and with a valve seat at the upper end of said cylindrical surface, and with a dome chamber above said valve seat, the Wall of said casing being formed with a pair of diametrically opposed, external openings and with cored passages connecting said openings with said cylindrical surface, the wall of said casing being furthermore formed with a passage connecting said cylindrical surface with said cylindrical member, a plunger slidably mounted within said casing having a flange portion within said cylindrical passage, and a body portion adapted to be received within said cylindrical surface, and a portion at its upper end adapted to contact said valve seat, said plunger being adapted to close said passages in the up position thereof and to uncover said passages in the down position thereof, means to connect said openings with the admission ports of said steam cylinder, a spring interposed between said plunger and the top of the casing, means to supply steam to the dome chamber of said casing, cylinder cocks on said steam cylinder, manually controlled means to supply air to said cylinder cocks, and means controlled by said manually controlled means, to control the supply of steam to the dome chamber of said steam balancing valve.

CHARLES STERN. 

